title: Molecular characteristics of community-acquired methicillin-resistant Staphylococcus aureus in Hokkaido, northern main island of Japan: identification of sequence types 6 and 59 Panton-Valentine leucocidin-positive community-acquired methicillin-resistant Staphylococcus aureus.
abstract: Prevalence and molecular characteristics of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) were studied in Hokkaido, the main northern island of Japan. Among the 1,015 S. aureus isolates derived from clinical specimens of outpatients collected in 2009, methicillin resistance gene mecA was detected in 189 isolates (18.6%). The most frequent staphylococcal cassette chromosome mec (SCCmec) type in MRSA was II (83.1%), followed by IV (6.9%) and V (3.2%). MRSA with type II-SCCmec showed multiple drug resistance and harbored various toxin and virulence factor genes except for Panton-Valentine leucocidin (PVL) gene. These isolates were mostly classified into sequence type 5 (ST5) (or other STs in CC5) and coagulase genotype II and were thus genetically similar to hospital-acquired MRSA, which have been predominating in Japan (New York/Japan clone). PVL gene was detected in three MRSA strains belonging to ST6 (two strains) and ST59 (one strain), having type IVa- and Vt-SCCmec, respectively, and also in two methicillin-susceptible S. aureus ST121 and ST188. The arcA gene within the arginine catabolic mobile element (ACME) was detected in the two PVL-negative ST5 MRSA strains, which had type IIa- or V-SCCmec. The PVL gene-positive ST6 and ST59 CA-MRSA strains were susceptible to more antimicrobials and had less virulence factor genes than the PVL-negative ST5 MRSA, including the ACME-arcA-positive strains. In the present study, ST6 was identified as a lineage of PVL-positive CA-MRSA, the ACME-arcA was first detected in ST5 MRSA with type V-SCCmec, and ST59 Taiwanese CA-MRSA strain was isolated in Hokkaido for the first time. These findings suggest a potential spread of these emerging CA-MRSA clones in Japan.
authors.affiliation: Department of Hygiene, Sapporo Medical University School of Medicine, Sapporo, Japan. kawaguchiya@sapmed.ac.jp
authors.forename: Mitsuyo
authors.initials: M
authors.lastname: Kawaguchiya
authors.forename: Noriko
authors.initials: N
authors.lastname: Urushibara
authors.forename: Osamu
authors.initials: O
authors.lastname: Kuwahara
authors.forename: Masahiko
authors.initials: M
authors.lastname: Ito
authors.forename: Keiji
authors.initials: K
authors.lastname: Mise
authors.forename: Nobumichi
authors.initials: N
authors.lastname: Kobayashi
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001427:Bacterial Toxins / Q000235:genetics* / Q000302:isolation & purification; D015373:Bacterial Typing Techniques; D001826:Body Fluids / Q000382:microbiology; D003030:Coagulase / Q000235:genetics; D017714:Community-Acquired Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology* / Q000635:transmission; D004269:DNA, Bacterial / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects / Q000235:genetics; D005098:Exotoxins / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D020071:Interspersed Repetitive Sequences; D007564:Japan; D007956:Leukocidins / Q000235:genetics* / Q000302:isolation & purification; D008712:Methicillin / Q000494:pharmacology*; D016106:Methicillin Resistance / Q000187:drug effects / Q000235:genetics; D055624:Methicillin-Resistant Staphylococcus aureus / Q000145:classification* / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification* / Q000472:pathogenicity; D008826:Microbial Sensitivity Tests; D015995:Prevalence; D013203:Staphylococcal Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology* / Q000635:transmission; D037521:Virulence Factors / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D001427:Bacterial Toxins; D003030:Coagulase; D004269:DNA, Bacterial; D005098:Exotoxins; D007956:Leukocidins; C078284:Panton-Valentine leukocidin; D037521:Virulence Factors; D008712:Methicillin